LCD or GPU problem

I had it before and i disassembled laptop, changed thermal paste and it was magically gone. But after some time it returned back. I tried to disassemble again but i brooked lcd cable. So i ordered a new hoping that the cable was the problem from the start. I replaced it and the problem is still there, you can see it on video.

HDMI and VGA output works, also in BIOS i see clear image, maybe just some noticeable flickering, maybe this is normal. Also in video you can see ASUS inscription is ok, only loading animation is distorted. Don't know why after ASUS logo loading screen, lcd goes wild.

Thank you for your advices! Don't have much trust in local repair workshops, they will say to change LCD panel or motherboard or something like that. I may do it, but i need to be shure that it will solve the problem.

3 Soluções

Just a thought before replacing the LCD clean the cable ends with IP alcohol . small bits of dirt or lint in the contacts can create a similar problem. If after cleaning you have no Joy then inspect the solder joints at the connection on the motherboard . Use a magnifying glass or loop for close inspection . look for cracks in the solder or missing pins is you see any cold solder joints cracks or dull solder . Use flux and a Hot air station to reflow the solder . If all seems well on the board end then try installing an new LCD. Hope this helps

Cable works fine for BIOS menu or when booting to WinPE from USB stick. Don't know what to think. I will try to connect a HDD with a Windows XP or Vista installed. I think the problem is UEFI firmware.

As long as an external monitor that is connected to either the HDMI or VGA interface works fine, the problem does not seem to be related to the GPU. You already replaced the cable, so the only item that seems to create the issue is the LCD itself. Like Claes pointed out, it is likely that the controller is defective, hopefully the controller on the back of the LCD panel.

the fun part is that if i boot from USB drive from, let's say, WinPE, then the screen works fine. The BIOS is fine. I think the problem may be in UEFI firmware, the glitches appears when Windows 8 is loading. I think it may have some interference with it. I will try to connect another HDD with Windos XP or something installed not on GPT

This is a problem with the Nvidia GPU. This is very common across the board with Toshibas, Dells, and other brands. The reason why an external monitor or HDMI work is because your Intel CPU has a built in graphics card of its own integrated.

What specs are you referring to? Both Discrete and integrated VGA are capable of handling HDMI. If you really want to go about the long and expensive way to diagnose this, get another LCD and another motherboard. If the LCD works, then the LCD is the problem. If the motherboard change worked, then the Nvidia was your problem or the connector from the motherboard to the LCD was bad. In both the Intel CPU with integrated graphics will remain the same because the CPU and Intel graphics are one and the same. You cannot simply change out the NVidia because it is soldered on.